SU1463134A3 - Method of producing ethanol - Google Patents

Abstract

A flow of fermenting liquor from a fermentor is separated into a yeast concentrate flow, which is recirculated to the fermentor, and a yeast-free flow which is separated in a simple evaporator unit into a first ethanol-enriched vapor flow and a first liquid bottom flow. The first vapor flow is treated to produce the desired ethanol while a major part of the first liquid bottom flow is recirculated to the fermentor. A minor, residual part of the latter flow is fed to a stripping unit where it is separated into a second ethanol-enriched vapor flow and a second liquid bottom flow exhausted of ethanol.

Description

one

This invention relates to the alcohol industry.

The aim of the invention is to reduce energy costs and prevent scale formation.

The wort is fermented, divided into a stream of yeast concentrate and fermented wort, the yeast concentrate is returned to the fermented wort, a vapor stream containing ethanol in the distillation, evaporation and desorption units is separated from the fermented wort, and the distillation stream is rectified in the distillation unit the column. The bard after the evaporation unit is divided into two parts, one of which is returned to the stage of fermentation of the wort, and the second part of the bard is subjected to separation in the desorption unit into an ethanol-rich vapor stream and vat residue. Part of the vapor stream is sent directly or indirectly to the distillation unit or mixed with a steam stream containing ethanol, obtained after its extraction from fermented wort, or it is used or the mixture is used to heat the rectification column. It is advisable after rectification formed

four

05

Od

with

four

cm.

the fluid flow is recirculated;

J. FIG. - 4 shows installation. to implement the method.

The installation includes a fermenter 1, iieHTpo6eKHbrft separator 2, an evaporative unit 3, a desorbed unit 4 and a distillate unit 5, pipelines 6-16, a scrubber 17 and a heat exchanger 18.

Example 1. According to FIG. 1, i: ycjio is fermented in a fermenter, in separator 2 it is divided into a stream of yeast concentrate and fermented: cond6. Yeast is recirculated through pipelines 6 and 7, and the fermented wort is directed through pipe 8 to the evaporator unit 3, where the 2GO is separated into a vapor stream containing ethanol and bard, which is transported through pipeline 9, - put into two parts, one of which is returned via pipeline 10 to the fermentation stage 1 to fermentor 1, and {circled through pipeline 1 1 is fed to desorption unit 4. The vapor stream, rich in ethanol, is fed through pipeline 12 to the distillation unit, where from the desorption unit 4 on. | Pipeline 13 also serves a steam stream. From the distillation unit, 5 is a stream of concentrated ethanol and a bottoms residue, consisting of: mostly from water and liberated more or less completely from ethanol. The cube residue can be used by vyshshaniem captured ethanol from a stream of carbon dioxide, as a result of fermentation, dp what it through pipeline 14 is fed into the scrubber 17, which through pipeline 15 from the fermenter 1 serves carbon dioxide. The resulting stream can be used to dilute the wort.

The evaporation unit consists of a short column corresponding to one or more distillation cascades, and the desorption unit consists of a desorption column having a slightly larger number of distillation cascades, for example, made in the form of plates.

Example 2. The method is carried out analogously to example 1, only according to FIG. 2, the desorption unit 4 consists of three evaporation cascades, arranged in series TciK, that the vat residue is presented sequentially and cascades, and the steam flow is returned from each subsequent stage to the previous one. The last stage is equipped with a heat exchanger 18 for indirectly supplying the energy required for desorption.

Example 3. The method is carried out analogously to example 1, only

according to FIG. 3, the evaporation unit 3 consists of a short column corresponding to one or more distillation cascades, and the desorption unit 4 consists of a desorption column with a slightly larger number of distillation cascades. The second stream of vapors, enriched with ethanol, is fed to the evaporation unit 3, from which the first stream of vapors leaves,

Q is enriched with ethanol, and it is fed through conduit 12 to a condenser 19, consisting of one or more condensation cascades, from the top of which a smaller flow of volatile is emitted

5 impurities, and from its bottom part through conduit 20 to the distillation-desorption column 21, equipped with a heater 22 and a refrigerator 23. From this column, a stream of eto NOL with a high ethanol content and a cubic residue with a low ethanol content are obtained. The energy for separation in the desorption unit 4 or in the evaporation unit 3 can be supplied through the heat exchanger 18 and the heater 24 or in the form of live steam in the evaporation unit 3.

Example 4, Fng, 4 presents an example of a material balance, where T is the full flow; -F is a fermentable wort; NF is a solid dissolving unbased material, mainly salts, glycerin and other Organic impurities are not separately taken into account; DS is the sum of F + NF, t, e, dry BeujecTBO, DS for feed supplied is equal to 42.7 wt.%, Including added water, DS in the fermenter is equal to 25.8 wt.% (Yeast is not taken into account), they

g is not included in the non-yeast stream fed to the evaporative unit. In the bard, DS is 27.0 wt.% And 35.1 wt.% In-waste, .22% bards are recycled to the fermenter with ethanol content of 2.8 wt.%. The energy for separation in the evaporation unit 3 and in the desorption unit 4 is served partly as indirect heating steam to the desorption unit 4 and partly

five

in the form of a pair of indirect heating or live steam from the outside into the evaporation unit 3.

Possible to work with DS from 25 to 30 May.7,

The proposed method allows to reduce energy consumption and stop scale formation in blocks.

Claims (2)

Claim 1. Method for producing ethanol, which includes fermenting the wort, dividing it into a stream of yeast concentrate and fermented wort, returning the yeast concentrate to the fermenting wort, separating the vapor stream containing ethanol in the distillation and evaporating units into the fermented wort to produce bards, rectification it in distillation (kx) cone and separation of bards into two parts, one of the first ones that are returned to the stage of fermentation of the wort, about 1 and 5, and so that, in order to reduce energy costs and prevent scale formation, the other part of the bards is subjected to separation in the stripping unit for vapor flow , enriched with ethanol, and still residue, In this case, part of the stream of vapors enriched in ethanol is sent to a distant block or mixed with a vapor stream containing ethanol obtained after its separation from fermented wort, or it is used or the mixture is used to heat the distillation column. 2. A method according to claim 1, characterized in that after rectifying a vapor stream containing ethanol, the resulting liquid stream is recycled to the evaporation unit. 23 PhieZ